A low-cost synthesis process for dimethyl 2,2-dimethylmalonate. The process is a two-step reaction. First, 2,2-dimethyl-1,3-propanediol is used as a starting material to oxidize it. The crude product was 2,2-dimethylmalonic acid and recrystallized to obtain pure 2,2-dimethylmalonic acid . Then, using Lewis acid as a catalyst, 2,2-dimethylmalonic acid is esterified with methanol, and the alkane is a water-carrying agent. After completion of the reaction, the solvent was distilled off and the product was washed with water, dried, and distilled under reduced pressure. See the instructions for a more detailed process. The invention has the characteristics that the process is environmentally friendly and the raw material cost is greatly reduced.